Expression Timeline
In the early placentae (6–8 weeks gestation), both parental H19 alleles (maternal and paternal) are expressed.
After 10 weeks gestation and in full term placentae, there is exclusive expression of H19 from the maternal chromosome. In the embryo, maternal expression of H19 is present in endodermal and mesodermal tissues. The regulated expression of H19, from biallelic to monoallelic, throughout embryonic development suggests that regulation is essential for the growth of embryonic and extraembryonic tissues. Immediately after birth, H19 expression is downregulated in all tissues except for skeletal muscle.
Studies by Tanos et al. suggest that the accumulation of H19 RNA in skeletal muscle cells is solely due to the stabilization of that RNA in the muscle cells during differentiation.
In females, H19 is expressed postnatally during puberty and pregnancy in the mammary glands, and in the uterus during pregnancy.
A study by Shoshani et al. suggests that H19 is continued to be expressed in high amounts in the liver after birth, specifically in diploid hepatocytes.
Read more about this topic: H19 (gene)
Famous quotes containing the word expression:
“Call them rules or call them limits, good ones, I believe, have this in common: They serve reasonable purposes; they are practical and within a child’s capability; they are consistent; and they are an expression of loving concern.”
—Fred Rogers (20th century)